Different sections on a semiconductor chip comprise electronic circuits with a plurality of structures that need to be electrically insulated from other parts of the semiconductor die. To this end, trenches are created around the respective structure. However, some structures require trenches that reach deeper into the substrate to fully provide insulation according to the respective specification. A variety of methods exists to create such isolation trenches within a semiconductor device. However, these conventional methods require further elaborate development if trenches with different depths on the same die are necessary.
Hence, there exists a need for an improved method providing formation of multiple depth shallow isolation trenches across a semiconductor die.